Small Interfering RNA to Reduce Lipoprotein(a) in Cardiovascular Disease

Lepodisiran, an Extended-Duration Short Interfering RNA Targeting Lipoprotein(a): A Randomized Dose-Ascending Clinical Trial

Importance

Epidemiological and genetic data have implicated lipoprotein(a) as a potentially modifiable risk factor for atherosclerotic disease and aortic stenosis, but there are no approved pharmacological treatments.

Objectives

To assess the safety, tolerability, pharmacokinetics, and effects of lepodisiran on lipoprotein(a) concentrations after single doses of the drug; lepodisiran is a short interfering RNA directed at hepatic synthesis of apolipoprotein(a), an essential component necessary for assembly of lipoprotein(a) particles.

Design, Setting, and Participants

A single ascending-dose trial conducted at 5 clinical research sites in the US and Singapore that enrolled 48 adults without cardiovascular disease and with lipoprotein(a) serum concentrations of 75 nmol/L or greater (or ≥30 mg/dL) between November 18, 2020, and December 7, 2021; the last follow-up visit occurred on November 9, 2022.

Interventions

Participants were randomized to receive placebo or a single dose of lepodisiran (4 mg, 12 mg, 32 mg, 96 mg, 304 mg, or 608 mg) administered subcutaneously.

Main Outcomes and Measures

The primary outcome was the safety and tolerability of the single ascending doses of lepodisiran. The secondary outcomes included plasma levels of lepodisiran for 168 days after dose administration and changes in fasting lipoprotein(a) serum concentrations through a maximum follow-up of 336 days (48 weeks).

Results

Of the 48 participants enrolled (mean age, 46.8 [SD, 11.6] years; 35% were women), 1 serious adverse event occurred. The plasma concentrations of lepodisiran reached peak levels within 10.5 hours and were undetectable by 48 hours. The median baseline lipoprotein(a) concentration was 111 nmol/L (IQR, 78 to 134 nmol/L) in the placebo group, 78 nmol/L (IQR, 50 to 152 nmol/L) in the 4 mg of lepodisiran group, 97 nmol/L (IQR, 86 to 107 nmol/L) in the 12-mg dose group, 120 nmol/L (IQR, 110 to 188 nmol/L) in the 32-mg dose group, 167 nmol/L (IQR, 124 to 189 nmol/L) in the 96-mg dose group, 96 nmol/L (IQR, 72 to 132 nmol/L) in the 304-mg dose group, and 130 nmol/L (IQR, 87 to 151 nmol/L) in the 608-mg dose group. The maximal median change in lipoprotein(a) concentration was -5% (IQR, -16% to 11%) in the placebo group, -41% (IQR, -47% to -20%) in the 4 mg of lepodisiran group, -59% (IQR, -66% to -53%) in the 12-mg dose group, -76% (IQR, -76% to -75%) in the 32-mg dose group, -90% (IQR, -94% to -85%) in the 96-mg dose group, -96% (IQR, -98% to -95%) in the 304-mg dose group, and -97% (IQR, -98% to -96%) in the 608-mg dose group. At day 337, the median change in lipoprotein(a) concentration was -94% (IQR, -94% to -85%) in the 608 mg of lepodisiran group.

Conclusions and Relevance

In this phase 1 study of 48 participants with elevated lipoprotein(a) levels, lepodisiran was well tolerated and produced dose-dependent, long-duration reductions in serum lipoprotein(a) concentrations. The findings support further study of lepodisiran.

Trial Registration

ClinicalTrials.gov Identifier: NCT04914546.

Emerging therapies in dyslipidaemias

Several observations have shown that elevated levels of low-density lipoprotein cholesterol (LDL-C) are a cause of cardiovascular disease. Lowering LDL-C is a key strategy for reducing cardiovascular risk, with a continuous linear correlation between LDL-C reduction and cardiovascular benefit. Based on these observations, current guidelines have further lowered LDL-C goals and call for the use of more effective therapeutic interventions. In addition to statins, ezetimibe and the monoclonal antibodies targeting PCSK9, several new lipid-lowering agents are currently in phase 3 clinical trials to evaluate their clinical effects, and more are in development. The use of combination therapies targeting different pathways can increase the effectiveness of treatment.

Highlights of Cardiovascular Disease Prevention Studies Presented at the 2023 European Society of Cardiology Congress

PURPOSE OF REVIEW

To summarize selected late-breaking science on cardiovascular (CV) disease prevention presented at the 2023 European Society of Cardiology (ESC) congress.

RECENT FINDINGS

The NATURE-PARADOX was a naturally randomized trial that used genetic data from the UK Biobank registry to create "cumulative exposure to low-density lipoprotein-cholesterol (LDL-C)" biomarker and evaluate its association with major CV events regardless of plasma LDL-C levels or age. Safety and efficacy data of inclisiran, a PCSK9-interfering mRNA (PCSK9i) administered subcutaneously twice annually, were presented. Data on two new PCSK9is were presented, recaticimab, an oral drug, and lerodalcibep, a subcutaneous drug with a slightly different architecture than currently available PSCK9is. A phase 1 trial on muvalaplin, an oral lipoprotein (a) inhibitor, was presented. An atherosclerotic CV disease (ASCVD) risk prediction algorithm for the Asian population using SCORE2 data was presented. Long-term follow-up of patients enrolled in the CLEAR outcomes trial showed sustained and more significant ASCVD risk reduction with bempedoic acid in high-risk patients. The late-breaking clinical science at the 2023 congress of the ESC extends the known safety and efficacy data of a PCSK9i with the introduction of new drugs in this class. Using cumulative exposure to LDL-C rather than a single value will help clinicians tailor the LDL-C reduction strategy to individual risk and is an important step towards personalized medicine.

Lipoprotein(a): a genetically determined risk factor for Cardiovascular disease

Lipoprotein(a) is a complex lipoprotein with unique characteristics distinguishing it from all the other apolipoprotein B-containing lipoprotein particles. Its lipid composition and the presence of a single molecule of apolipoprotein B per particle, render lipoprotein(a) similar to low-density lipoproteins. However, the presence of a unique, carbohydrate-rich protein termed apolipoprotein(a), linked by a covalent bond to apolipoprotein B imparts unique characteristics to lipoprotein(a) distinguishing it from all the other lipoproteins. Apolipoprotein(a) is highly polymorphic in size ranging in molecular weight from <300 KDa to >800 kDa. Both the size polymorphism and the concentration of lipoprotein(a) in plasma are genetically determined and unlike other lipoproteins, plasma concentration is minimally impacted by lifestyle modifications or lipid-lowering drugs. Many studies involving hundreds of thousands of individuals have provided strong evidence that elevated lipoprotein(a) is genetically determined and a causal risk factor for atherosclerotic cardiovascular disease. The concentration attained in adulthood is already present in children at around 5 years of age and therefore, those with elevated lipoprotein(a) are prematurely exposed to a high risk of cardiovascular disease. Despite the large number of guidelines and consensus statements on the management of lipoprotein(a) in atherosclerotic cardiovascular disease published in the last decade, lipoprotein(a) is still seldom measured in clinical settings. In this review, we provide an overview of the most important features that characterize lipoprotein(a), its role in cardiovascular disease, and the importance of adding the measurement of lipoprotein(a) for screening adults and youths to identify those at increased risk of atherosclerotic cardiovascular disease due to their elevated plasma concentration of lipoprotein(a).

Primary Prevention of Subclinical Atherosclerosis in Young Adults: JACC Review Topic of the Week

There is growing evidence that the atherosclerotic process that leads to symptomatic cardiovascular disease (CVD) starts at an early age. In young adults, exposure to low-density lipoprotein-cholesterol and other cardiovascular risk factor (CVRF) mediators, even at levels considered within normal limits, increases the prevalence of subclinical atherosclerosis and is associated with greater risk of cardiovascular events later in life. The optimal CVRF targets to prevent CVD in asymptomatic young individuals (<40 years) are unknown. The randomized controlled PRECAD (Prevent Coronary Artery Disease) trial has been developed to assess the potential benefit of an aggressive control of CVRF in otherwise healthy young adults. The hypothesis of PRECAD is that in subjects aged 20 to 39 years without known CVD, maintaining low-density lipoprotein-cholesterol <70 mg/dL and strict control of blood pressure and glucose will prevent the onset of atherosclerosis and/or its progression. The primary endpoint will be the change in total atherosclerosis burden, a surrogate for CVD.

Bibliometric analysis of residual cardiovascular risk: trends and frontiers

BACKGROUND

The presence of residual cardiovascular risk is an important cause of cardiovascular events. Despite the significant advances in our understanding of residual cardiovascular risk, a comprehensive analysis through bibliometrics has not been performed to date. Our objective is to conduct bibliometric studies to analyze and visualize the current research hotspots and trends related to residual cardiovascular risk. This will aid in understanding the future directions of both basic and clinical research in this area.

METHODS

The literature was obtained from the Web of Science Core Collection database. The literature search date was September 28, 2022. Bibliometric indicators were analyzed using CiteSpace, VOSviewer, Bibliometrix (an R package), and Microsoft Excel.

RESULT

A total of 1167 papers were included, and the number of publications is increasing rapidly in recent years. The United States and Harvard Medical School are the leading country and institution, respectively, in the study of residual cardiovascular risk. Ridker PM and Boden WE are outstanding investigators in this field. According to our research results, the New England Journal of Medicine is the most influential journal in the field of residual cardiovascular risk, whereas Atherosclerosis boasts the highest number of publications on this topic. Analysis of keywords and landmark literature identified current research hotspots including complications of residual cardiovascular risk, risk factors, and pharmacological prevention strategies.

CONCLUSION

In recent times, global attention toward residual cardiovascular risk has significantly increased. Current research is focused on comprehensive lipid-lowering, residual inflammation risk, and dual-pathway inhibition strategies. Future efforts should emphasize strengthening international communication and cooperation to promote the comprehensive evaluation and management of residual cardiovascular risk.

Updates in Small Interfering RNA for the Treatment of Dyslipidemias

PURPOSE OF REVIEW

Atherosclerotic cardiovascular disease (ASCVD) is still the leading cause of death worldwide. Despite excellent pharmacological approaches, clinical registries consistently show that many people with dyslipidemia do not achieve optimal management, and many of them are treated with low-intensity lipid-lowering therapies. Beyond the well-known association between low-density lipoprotein cholesterol (LDL-C) and cardiovascular prevention, the atherogenicity of lipoprotein(a) and the impact of triglyceride (TG)-rich lipoproteins cannot be overlooked. Within this landscape, the use of RNA-based therapies can help the treatment of difficult to target lipid disorders.

RECENT FINDINGS

The safety and efficacy of LDL-C lowering with the siRNA inclisiran has been documented in the open-label ORION-3 trial, with a follow-up of 4 years. While the outcome trial is pending, a pooled analysis of ORION-9, ORION-10, and ORION-11 has shown the potential of inclisiran to reduce composite major adverse cardiovascular events. Concerning lipoprotein(a), data of OCEAN(a)-DOSE trial with olpasiran show a dose-dependent drop in lipoprotein(a) levels with an optimal pharmacodynamic profile when administered every 12 weeks. Concerning TG lowering, although ARO-APOC3 and ARO-ANG3 are effective to lower apolipoprotein(apo)C-III and angiopoietin-like 3 (ANGPTL3) levels, these drugs are still in their infancy. In the era moving toward a personalized risk management, the use of siRNA represents a blossoming armamentarium to tackle dyslipidaemias for ASCVD risk reduction.

Coronary artery calcium and sudden cardiac death: current evidence and future directions

PURPOSE OF REVIEW

To provide a summary of the current evidence and highlight future directions regarding coronary artery calcium (CAC) and risk of sudden cardiac death (SCD).

RECENT FINDINGS

Although up to 80% of all SCD is attributed to coronary heart disease (CHD), the subclinical atherosclerosis markers that help to improve SCD risk prediction are largely unknown. Recent observational data have demonstrated that, after adjustment for traditional risk factors, there is a stepwise higher risk for SCD across increasing CAC burden such that asymptomatic patients without overt atherosclerotic cardiovascular disease (ASCVD) experience a three-fold to five-fold higher SCD risk beginning at CAC at least 100 when compared with CAC = 0. Although the mechanisms underlying increasing CAC and SCD risk have yet to be fully elucidated, risk for myocardial infarction and scar, and/or exercise-induced ischemia may be potential mediators.

SUMMARY

High CAC burden is an important risk factor for SCD in asymptomatic middle-aged adults, suggesting that SCD risk stratification can begin in the early stages of CHD via measurement of calcific plaque on noncontrast computed tomography. Despite the clinical inertia for downstream functional cardiac testing after detecting high CAC, comprehensive ASCVD prevention strategies should be the primary focus for SCD risk reduction.

[Update on lipid lowering therapy in peripheral artery disease]

Despite clear guideline recommendations, only about every second PAD patient is prescribed statins, women less often than men. There is an international consensus that every PAD patient should be treated with statins, as these not only lower lipids but also stabilize plaque, resulting in a prognostic benefit. Limb-related endpoints (MALE) can be reduced by 24% compared to placebo by lowering lipids. The combination of low-dose, high-potency statin with ezetimibe can be equivalent to high-dose statin monotherapy and, with better tolerability, promote therapy adherence. Statin intolerance is observed more frequently in certain risk groups but is very rare overall. Effective alternatives are bempedoic acid and PCSK9 inhibitors. About 20% of the population have severely elevated Lp(a) levels that require risk factor management beyond lipid management. A high Lp(a) concentration is associated with PAD progression as an independent risk factor for all atherosclerosis manifestations. Every adult should have an Lp(a) assessment once in their lifetime.

The Promise of PCSK9 and Lipoprotein(a) as Targets for Gene Silencing Therapies

PURPOSE

High plasma concentrations of LDL and lipoprotein(a) (Lp[a]) are independent and causal risk factors for atherosclerotic cardiovascular disease (ASCVD). There is an unmet therapeutic need for high-risk patients with elevated levels of LDL-C and/or Lp(a). Recent advances in the development of nucleic acids for gene silencing (ie, triantennary N-acetylgalactosamine conjugated antisense-oligonucleotides [ASOs] and small interfering RNA [siRNA]) targeting proprotein convertase subtilisin/kexin type 9 (PCSK9) and Lp(a) offer effective and sustainable therapies.

METHODS

Related articles in the English language were identified through a search for original and review articles in the PubMed database using the following key terms: cardiovascular disease, dyslipidemia, PCSK9 inhibitors, Lp(a), LDL-cholesterol, familial hypercholesterolemia, siRNA, and antisense oligonucleotide and clinical trials (either alone or in combination).

FINDINGS

Inclisiran, the most advanced siRNA-treatment targeting hepatic PCSK9, is well tolerated, producing a >30% reduction on LDL-C levels in randomized controlled trials. Pelacarsen is the most clinical advanced ASO, whereas olpasiran and SLN360 are the 2 siRNAs directed against the mRNA of the LPA gene. Evidence suggests that all Lp(a)-targeting agents are safe and well tolerated, with robust and sustained reduction in plasma Lp(a) concentration up to 70% to 90% in individuals with elevated Lp(a) levels.

IMPLICATIONS

Cumulative evidence from clinical trials supports the value of ASO and siRNA therapies targeting the synthesis of PCSK9 and Lp(a) for lowering LDL-C and Lp(a) in patients with established ASCVD or high risk of ASCVD. Further research is needed to examine whether gene silencing therapy could improve clinical outcomes in patients with elevated LDL and/or Lp(a) levels. Confirmation of the tolerability and cost-effectiveness of long-term inhibition of PCSK9 and Lp(a) with this approach is essential.

Novel Pharmacological Approaches in the Treatment of Hypertension: A Focus on RNA-Based Therapeutics

Hypertension remains the leading cause of cardiovascular disease and premature death globally, affecting half of US adults. A high proportion of hypertensive patients exhibit uncontrolled blood pressure (BP), associated with poor adherence, linked to pill burden and adverse effects. Novel pharmacological strategies are urgently needed to improve BP control. Dysregulation of the renin-angiotensin system increases BP through its primary effector, Ang II (angiotensin II), which results in tissue remodeling and end-organ damage. Silencing liver angiotensinogen (the sole source of Ang II) has been achieved using novel RNA therapeutics, including the antisense oligonucleotide, IONIS-AGT (angiotensinogen)-LRX, and the small-interfering RNA, zilebesiran. Conjugation to N-acetylgalactosamine enables targeted delivery to hepatocytes, where endosomal storage, slow leakage, and small-interfering RNA recycling (for zilebesiran) result in knockdown over several months. Indeed, zilebesiran has an impressive and durable effect on systolic BP, reduced by up to 20 mm Hg and sustained for 6 months after a single administration, likely due to its very effective knockdown of angiotensinogen, without causing acute kidney injury or hyperkalemia. By contrast, IONIS-AGT-LRX caused less knockdown and marginal effects on BP. Future studies should evaluate any loss of efficacy relating to antidrug antibodies, safety issues associated with long-term angiotensinogen suppression, and broader benefits, especially in the context of common comorbidities such as type 2 diabetes and chronic kidney disease.

Changes in Lipoprotein(a) Levels in People after ST Elevation Myocardial Infarction-The STEMI-Lipids Study

Lipoprotein(a) (Lp(a)) is considered an independent risk factor for cardiovascular diseases. The plasma concentration of Lp(a) is largely genetically determined but varies over a wide range within the population. This study investigated changes in Lp(a) levels after an acute myocardial infarction. Patients who underwent coronary angiography due to an ST elevation myocardial infarction were enrolled (n = 86), and Lp(a) levels were measured immediately after the intervention, one day, two days, and at a post-discharge follow-up visit at 3 to 6 months after the acute myocardial infarction. Median Lp(a) levels increased from a median of 7.9 mg/dL (3.8-37.1) at hospital admission to 8.4 mg/dL (3.9-35.4) on the following day, then to 9.3 mg/dL (3.7-39.1) on day two (p < 0.001), and to 11.2 mg/dL (4.4-59.6) at the post-discharge follow-up (p < 0.001). Lp(a) levels were the lowest during the acute myocardial infarction and started to increase significantly immediately thereafter, with the highest levels at the post-discharge follow-up. The moderate but significant increase in Lp(a) in people with acute myocardial infarction appears to be clinically relevant on an individual basis, especially when specific Lp(a) cut-off levels are supposed to determine the initiation of future treatment. Hence, a repeated measurement of Lp(a) after myocardial infarction should be performed.

Lipoprotein(a) and functional outcome of acute ischemic stroke when discordant with low-density lipoprotein cholesterol

BACKGROUND

Several studies have indicated that residual cardiovascular risk might be associated with elevated lipoprotein(a) [Lp(a)] even in the setting of controlled low-density lipoprotein cholesterol (LDL-C). We aimed to prospectively examine the association between Lp(a) and unfavorable functional outcome among patients with acute ischemic stroke when Lp(a) and LDL-C were discordant.

METHODS

Based on samples from the Infectious Factors, Inflammatory Markers and Prognosis of Acute Ischemic Stroke study, 973 patients with baseline plasma Lp(a) levels were included. The primary outcome was the composite outcome of death or major disability (modified Rankin Scale score of 3-6) at 6 months. Logistic regression models were used to estimate the risk for the primary outcome. Discordance analyses were performed, using difference in percentile units (>10 units), to detect the relative risk when Lp(a) and LDL-C were discordant.

RESULTS

In total, 201 (20.7%) participants experienced major disability or death at 6 months. The multivariable-adjusted odds ratio (OR) for the highest quartile was 1.88 [95% confidence interval (CI): 1.16-3.04] compared with the lowest quartile. Each 1-SD higher log-Lp(a) was associated with a 23% increased risk (95% CI: 2%-47%) for the primary outcome. Compared with the concordant group, the high Lp(a)/low LDL-C discordant group was associated with increased risk for the primary outcome (adjusted OR: 1.59, 95% CI: 1.01-2.52).

CONCLUSIONS

Elevated plasma Lp(a) levels were associated with increased risk of major disability and death at 6 months. Discordantly high Lp(a)/low LDL-C was associated with an unfavorable functional outcome, supporting the predictive potential of plasma Lp(a) after ischemic stroke, especially when discordant with LDL-C. Key messages What is already known on this topic Previous studies have indicated that a positive association between increased lipoprotein(a) [Lp(a)] and cardiovascular disease risk remained even in patients who achieved controlled low-density lipoprotein cholesterol (LDL-C) levels. The findings of studies exploring the association between Lp(a) and unfavorable clinical outcomes of stroke were inconsistent, and whether Lp(a) can predict the risk of unfavorable functional outcome in stroke patients when Lp(a) and LDL-C levels are discordant remains unknown. What this study adds Elevated plasma Lp(a) levels were associated with increased risk of major disability and death at 6 months beyond LDL-C levels in acute ischemic stroke patients. How this study might affect research, practice, or policy The combination of LDL-C-lowering therapies and Lp(a)-lowering therapies may have better clinical efficacy for patients with ischemic stroke, and it is of great clinical interest to further explore this possibility in dedicated randomized trials.

High residual cardiovascular risk after lipid-lowering: prime time for Predictive, Preventive, Personalized, Participatory, and Psycho-cognitive medicine

As time has come to translate trial results into individualized medical diagnosis and therapy, we analyzed how to minimize residual risk of cardiovascular disease (CVD) by reviewing papers on "residual cardiovascular disease risk". During this review process we found 989 papers that started off with residual CVD risk after initiating statin therapy, continued with papers on residual CVD risk after initiating therapy to increase high-density lipoprotein-cholesterol (HDL-C), followed by papers on residual CVD risk after initiating therapy to decrease triglyceride (TG) levels. Later on, papers dealing with elevated levels of lipoprotein remnants and lipoprotein(a) [Lp(a)] reported new risk factors of residual CVD risk. And as new risk factors are being discovered and new therapies are being tested, residual CVD risk will be reduced further. As we move from CVD risk reduction to improvement of patient management, a paradigm shift from a reductionistic approach towards a holistic approach is required. To that purpose, a personalized treatment dependent on the individual's CVD risk factors including lipid profile abnormalities should be configured, along the line of P5 medicine for each individual patient, i.e., with Predictive, Preventive, Personalized, Participatory, and Psycho-cognitive approaches.

Lp(a) in the Pathogenesis of Aortic Stenosis and Approach to Therapy with Antisense Oligonucleotides or Short Interfering RNA

To date, no medical therapy can slow the progression of aortic stenosis. Fibrocalcific stenosis is the most frequent form in the general population and affects about 6% of the elderly population. Over the years, diagnosis has evolved thanks to echocardiography and computed tomography assessments. The application of artificial intelligence to electrocardiography could further implement early diagnosis. Patients with severe aortic stenosis, especially symptomatic patients, have valve repair as their only therapeutic option by surgical or percutaneous technique (TAVI). The discovery that the pathogenetic mechanism of aortic stenosis is similar to the atherosclerosis process has made it possible to evaluate the hypothesis of medical therapy for aortic stenosis. Several drugs have been tested to reduce low-density lipoprotein (LDL) and lipoprotein(a) (Lp(a)) levels, inflammation, and calcification. The Proprotein Convertase Subtilisin/Kexin type 9 inhibitors (PCSK9-i) could decrease the progression of aortic stenosis and the requirement for valve implantation. Great interest is related to circulating Lp(a) levels as causally linked to degenerative aortic stenosis. New therapies with ASO (antisense oligonucleotides) and siRNA (small interfering RNA) are currently being tested. Olpasiran and pelacarsen reduce circulating Lp(a) levels by 85-90%. Phase 3 studies are underway to evaluate the effect of these drugs on cardiovascular events (cardiovascular death, non-fatal myocardial injury, and non-fatal stroke) in patients with elevated Lp(a) and CVD (cardiovascular diseases). For instance, if a reduction in Lp(a) levels is associated with aortic stenosis prevention or progression, further prospective clinical trials are warranted to confirm this observation in this high-risk population.

Role of lipoprotein(a) in atherosclerotic cardiovascular disease: A review of current and emerging therapies

Lipoprotein(a), or Lp(a), is structurally like low-density lipoprotein (LDL) but differs in that it contains glycoprotein apolipoprotein(a) [apo(a)]. Due to its prothrombotic and proinflammatory properties, Lp(a) is an independent risk factor for atherosclerotic cardiovascular disease (ASCVD) and aortic valve stenosis. Lp(a) levels are genetically determined, and it is estimated that 20%-25% of the global population has an Lp(a) level ≥50 mg/dL (or ≥125 nmol/L). Diet and lifestyle interventions have little to no effect on Lp(a) levels. Lipoprotein apheresis is the only approved treatment for elevated Lp(a) but is time-intensive for the patient and only modestly effective. Pharmacological approaches to reduce Lp(a) levels and its associated risks are of significant interest; however, currently available lipid-lowering therapies have limited effectiveness in reducing Lp(a) levels. Although statins are first-line agents to reduce LDL cholesterol levels, they modestly increase Lp(a) levels and have not been shown to change Lp(a)-mediated ASCVD risk. Alirocumab, evolocumab, and inclisiran reduce Lp(a) levels by 20-25%, yet the clinical implications of this reduction for Lp(a)-mediated ASCVD risk are uncertain. Niacin also lowers Lp(a) levels; however, its effectiveness in mitigating Lp(a)-mediated ASCVD risk remains unclear, and its side effects have limited its utilization. Recommendations for when to screen and how to manage individuals with elevated Lp(a) vary widely between national and international guidelines and scientific statements. Three investigational compounds targeting Lp(a), including small interfering RNA (siRNA) agents (olpasiran, SLN360) and an antisense oligonucleotide (pelacarsen), are in various stages of development. These compounds block the translation of messenger RNA (mRNA) into apo(a), a key structural component of Lp(a), thereby substantially reducing Lp(a) synthesis in the liver. The purpose of this review is to describe current recommendations for screening and managing elevated Lp(a), describe the effects of currently available lipid-lowering therapies on Lp(a) levels, and provide insight into emerging therapies targeting Lp(a).

Is Lipoprotein(a) Clinically Actionable with Today's Evidence? The Answer is Yes

PURPOSE OF REVIEW

Lipoprotein(a) is an independent risk factor for cardiovascular disease. We review the ongoing shifts in consensus guidelines for the testing and management of Lp(a) and provide insight into whether current evidence suggests that awareness and testing of Lp(a) is clinically actionable.

RECENT FINDINGS

GWAS and Mendelian randomization studies have established causal links between elevated Lp(a) and forms of CVD, including CAD and calcific aortic valve disease. Testing of Lp(a) identifies patients with similar risk to that of heterozygous FH, enhances risk stratification in patients with borderline/intermediate risk as determined through traditional factors, and facilitates the assessment of inherited CVD risk through cascade screening in patients with known family history of elevated Lp(a). Reductions in Lp(a) through non-targeted therapies including PCSK9 inhibition and lipoprotein apheresis have demonstrated reductions in ASCVD risk that are likely attributable to lowering Lp(a). Targeted therapies to potently lower Lp(a) are in clinical development. Lp(a) is actionable, and can be used to identify high risk patients for primary prevention and their family members through cascade screening, and to guide intensification of therapy in primary and secondary prevention of ASCVD.

Treatment of Lp(a): Is It the Future or Are We Ready Today?

PURPOSE OF REVIEW

The goal of this review is to present the pharmacodynamic effectiveness as well as the clinical efficacy and safety of investigational antisense oligonucleotides (ASOs) and small interference RNAs (siRNAs) drugs that specifically target lipoprotein(a) (Lp(a)). The review will discuss whether the existing lipid-lowering therapies are adequate to treat high Lp(a) levels or whether it is necessary to use the emerging new therapeutic approaches which are based on the current RNA technologies.

RECENT FINDINGS

Lipoprotein(a) (Lp(a)) is a causal risk factor for atherosclerotic cardiovascular disease (ASCVD), independent of other conventional risk factors. High Lp(a) levels are also independently associated with an increased risk of aortic stenosis progression rate. Plasma Lp(a) levels are primarily genetically determined by variation in the LPA gene coding for apo(a). All secondary prevention trials have demonstrated that the existing hypolipidemic therapies are not adequate to reduce Lp(a) levels to such an extent that could lead to a substantial reduction of ASCVD risk. This has led to the development of new drugs that target the mRNA transcript of LPA and efficiently inhibit Lp(a) synthesis leading to potent Lp(a) reduction. These new drugs are the ASO pelacarsen and the siRNAs olpasiran and SLN360. Recent pharmacodynamic studies showed that all these drugs potently reduce Lp(a) up to 98%, in a dose-dependent manner. Ongoing clinical trials will determine the Lp(a)-lowering efficacy, tolerability, and safety of these drugs as well as their potential effectiveness in reducing the ASCVD risk attributed to high plasma Lp(a) levels. We are not ready today to significantly reduce plasma Lp(a). Emerging therapies potently decrease Lp(a) and ongoing clinical trials will determine their effectiveness in reducing ASCVD risk in subjects with high Lp(a) levels.

European guidelines for the treatment of dyslipidaemias: New concepts and future challenges

Atherosclerotic cardiovascular disease (ASCVD) is the leading cause of mortality and morbidity worldwide. Low-density lipoprotein cholesterol (LDL-C) is one of the most important causal factors for ASCVD. Based on the evidence of the clinical benefits of lowering LDL-C, the current 2019 European Society of Cardiology (ESC) and European Atherosclerosis Society (EAS) guidelines provide guidance for optimal management of people with dyslipidaemia. These guidelines include new and revised concepts, with a general tightening of LDL-C goals to be achieved, especially for patients at high and very high cardiovascular risk, based on the results of clinical trials of the recently approved drugs for the treatment of hypercholesterolaemia. However, some issues are still open for discussion. Among others, the concept of lifetime exposure to elevated LDL-C levels will probably drive the pharmacological approach and future guidelines. In addition, other factors such as non-HDL-C, apolipoprotein B, and lipoprotein(a) are becoming increasingly important in determining cardiovascular risk. Finally, there is the question of whether combination therapy should be used as the first step to maximise the effectiveness of the pharmacological approach, avoiding the stepwise approach, which is likely to have a detrimental effect on adherence. Given the ever-changing landscape and the availability of new drugs targeting other important lipids, future guidelines will need to consider all these issues.

Muvalaplin, an Oral Small Molecule Inhibitor of Lipoprotein(a) Formation: A Randomized Clinical Trial

Importance

Lipoprotein(a) (Lp[a]) is associated with atherosclerotic disease and aortic stenosis. Lp(a) forms by bonding between apolipoprotein(a) (apo[a]) and apo B100. Muvalaplin is an orally administered small molecule that inhibits Lp(a) formation by blocking the apo(a)-apo B100 interaction while avoiding interaction with a homologous protein, plasminogen.

Objective

To determine the safety, tolerability, pharmacokinetics, and pharmacodynamic effects of muvalaplin.

Design, Setting, and Participants

This phase 1 randomized, double-blind, parallel-design study enrolled 114 participants (55 assigned to a single-ascending dose; 59 assigned to a multiple-ascending dose group) at 1 site in the Netherlands.

Interventions

The single ascending dose treatment evaluated the effect of a single dose of muvalaplin ranging from 1 mg to 800 mg or placebo taken by healthy participants with any Lp(a) level. The multiple ascending dose treatment evaluated the effect of taking daily doses of muvalaplin (30 mg to 800 mg) or placebo for 14 days in patients with Lp(a) levels of 30 mg/dL or higher.

Main Outcomes and Measures

Outcomes included safety, tolerability, pharmacokinetics, and exploratory pharmacodynamic biomarkers.

Results

Among 114 randomized (55 in the single ascending dose group: mean [SD] age, 29 [10] years, 35 females [64%], 2 American Indian or Alaska Native [4%], 50 White [91%], 3 multiracial [5%]; 59 in the multiple ascending dose group: mean [SD] age 32 [15] years; 34 females [58%]; 3 American Indian or Alaska Native [5%], 6 Black [10%], 47 White [80%], 3 multiracial [5%]), 105 completed the trial. Muvalaplin was not associated with tolerability concerns or clinically significant adverse effects. Oral doses of 30 mg to 800 mg for 14 days resulted in increasing muvalaplin plasma concentrations and half-life ranging from 70 to 414 hours. Muvalaplin lowered Lp(a) plasma levels within 24 hours after the first dose, with further Lp(a) reduction on repeated dosing. Maximum placebo-adjusted Lp(a) reduction was 63% to 65%, resulting in Lp(a) plasma levels less than 50 mg/dL in 93% of participants, with similar effects at daily doses of 100 mg or more. No clinically significant changes in plasminogen levels or activity were observed.

Conclusion

Muvalaplin, a selective small molecule inhibitor of Lp(a) formation, was not associated with tolerability concerns and lowered Lp(a) levels up to 65% following daily administration for 14 days. Longer and larger trials will be required to further evaluate safety, tolerability, and effect of muvalaplin on Lp(a) levels and cardiovascular outcomes.

Trial Registration

ClinicalTrials.gov Identifier: NCT04472676.

Development and Multinational Validation of a Novel Algorithmic Strategy for High Lp(a) Screening

Importance

Elevated lipoprotein(a) [Lp(a)] is associated with atherosclerotic cardiovascular disease (ASCVD) and major adverse cardiovascular events (MACE). However, fewer than 0.5% of patients undergo Lp(a) testing, limiting the evaluation and use of novel targeted therapeutics currently under development.

Objective

We developed and validated a machine learning model to enable targeted screening for elevated Lp(a).

Design

Cross-sectional.

Setting

4 multinational population-based cohorts.

Participants

We included 456,815 participants from the UK Biobank (UKB), the largest cohort with protocolized Lp(a) testing for model development. The model's external validity was assessed in Atherosclerosis Risk in Communities (ARIC) (N=14,484), Coronary Artery Risk Development in Young Adults (CARDIA) (N=4,124), and Multi-Ethnic Study of Atherosclerosis (MESA) (N=4,672) cohorts.

Exposures

Demographics, medications, diagnoses, procedures, vitals, and laboratory measurements from UKB and linked electronic health records (EHR) were candidate input features to predict high Lp(a). We used the pooled cohort equations (PCE), an ASCVD risk marker, as a comparator to identify elevated Lp(a).

Main Outcomes and Measures

The main outcome was elevated Lp(a) (≥150 nmol/L), and the number-needed-to-test (NNT) to find one case with elevated Lp(a). We explored the association of the model's prediction probabilities with all-cause and cardiovascular mortality, and MACE.

Results

The Algorithmic Risk Inspection for Screening Elevated Lp(a) (ARISE) used low-density lipoprotein cholesterol, statin use, triglycerides, high-density lipoprotein cholesterol, history of ASCVD, and anti-hypertensive medication use as input features. ARISE outperformed cardiovascular risk stratification through PCE for predicting elevated Lp(a) with a significantly lower NNT (4.0 versus 8.0 [with or without PCE], P<0.001). ARISE performed comparably across external validation cohorts and subgroups, reducing the NNT by up to 67.3%, depending on the probability threshold. Over a median follow-up of 4.2 years, a high ARISE probability was also associated with a greater hazard of all-cause death and MACE (age/sex-adjusted hazard ratio [aHR], 1.35, and 1.38, respectively, P<0.001), with a greater increase in cardiovascular mortality (aHR, 2.17, P<0.001).

Conclusions and Relevance

ARISE optimizes screening for elevated Lp(a) using commonly available clinical features. ARISE can be deployed in EHR and other settings to encourage greater Lp(a) testing and to improve identifying cases eligible for novel targeted therapeutics in trials.

KEY POINTS

Question: How can we optimize the identification of individuals with elevated lipoprotein(a) [Lp(a)] who may be eligible for novel targeted therapeutics?Findings: Using 4 multinational population-based cohorts, we developed and validated a machine learning model, Algorithmic Risk Inspection for Screening Elevated Lp(a) (ARISE), to enable targeted screening for elevated Lp(a). In contrast to the pooled cohort equations that do not identify those with elevated Lp(a), ARISE reduces the "number-needed-to-test" to find one case with elevated Lp(a) by up to 67.3%.Meaning: ARISE can be deployed in electronic health records and other settings to enable greater yield of Lp(a) testing, thereby improving the identification of individuals with elevated Lp(a).

Lipoprotein(a) as a Risk Factor for Cardiovascular Diseases: Pathophysiology and Treatment Perspectives

Cardiovascular disease (CVD) is still a leading cause of morbidity and mortality, despite all the progress achieved as regards to both prevention and treatment. Having high levels of lipoprotein(a) [Lp(a)] is a risk factor for cardiovascular disease that operates independently. It can increase the risk of developing cardiovascular disease even when LDL cholesterol (LDL-C) levels are within the recommended range, which is referred to as residual cardiovascular risk. Lp(a) is an LDL-like particle present in human plasma, in which a large plasminogen-like glycoprotein, apolipoprotein(a) [Apo(a)], is covalently bound to Apo B100 via one disulfide bridge. Apo(a) contains one plasminogen-like kringle V structure, a variable number of plasminogen-like kringle IV structures (types 1-10), and one inactive protease region. There is a large inter-individual variation of plasma concentrations of Lp(a), mainly ascribable to genetic variants in the Lp(a) gene: in the general po-pulation, Lp(a) levels can range from <1 mg/dL to >1000 mg/dL. Concentrations also vary between different ethnicities. Lp(a) has been established as one of the risk factors that play an important role in the development of atherosclerotic plaque. Indeed, high concentrations of Lp(a) have been related to a greater risk of ischemic CVD, aortic valve stenosis, and heart failure. The threshold value has been set at 50 mg/dL, but the risk may increase already at levels above 30 mg/dL. Although there is a well-established and strong link between high Lp(a) levels and coronary as well as cerebrovascular disease, the evidence regarding incident peripheral arterial disease and carotid atherosclerosis is not as conclusive. Because lifestyle changes and standard lipid-lowering treatments, such as statins, niacin, and cholesteryl ester transfer protein inhibitors, are not highly effective in reducing Lp(a) levels, there is increased interest in developing new drugs that can address this issue. PCSK9 inhibitors seem to be capable of reducing Lp(a) levels by 25-30%. Mipomersen decreases Lp(a) levels by 25-40%, but its use is burdened with important side effects. At the current time, the most effective and tolerated treatment for patients with a high Lp(a) plasma level is apheresis, while antisense oligonucleotides, small interfering RNAs, and microRNAs, which reduce Lp(a) levels by targeting RNA molecules and regulating gene expression as well as protein production levels, are the most widely explored and promising perspectives. The aim of this review is to provide an update on the current state of the art with regard to Lp(a) pathophysiological mechanisms, focusing on the most effective strategies for lowering Lp(a), including new emerging alternative therapies. The purpose of this manuscript is to improve the management of hyperlipoproteinemia(a) in order to achieve better control of the residual cardiovascular risk, which remains unacceptably high.

Novel Pharmacological Therapies for the Management of Hyperlipoproteinemia(a)

Lipoprotein(a) [Lp(a)] is a well-established risk factor for cardiovascular disease, predisposing to major cardiovascular events, including coronary heart disease, stroke, aortic valve calcification and abdominal aortic aneurysm. Lp(a) is differentiated from other lipoprotein molecules through apolipoprotein(a), which possesses atherogenic and antithrombolytic properties attributed to its structure. Lp(a) levels are mostly genetically predetermined and influenced by the size of LPA gene variants, with smaller isoforms resulting in a greater synthesis rate of apo(a) and, ultimately, elevated Lp(a) levels. As a result, serum Lp(a) levels may highly vary from extremely low to extremely high. Hyperlipoproteinemia(a) is defined as Lp(a) levels > 30 mg/dL in the US and >50 mg/dL in Europe. Because of its association with CVD, Lp(a) levels should be measured at least once a lifetime in adults. The ultimate goal is to identify individuals with increased risk of CVD and intervene accordingly. Traditional pharmacological interventions like niacin, statins, ezetimibe, aspirin, PCSK-9 inhibitors, mipomersen, estrogens and CETP inhibitors have not yet yielded satisfactory results. The mean Lp(a) reduction, if any, is barely 50% for all agents, with statins increasing Lp(a) levels, whereas a reduction of 80-90% appears to be required to achieve a significant decrease in major cardiovascular events. Novel RNA-interfering agents that specifically target hepatocytes are aimed in this direction. Pelacarsen is an antisense oligonucleotide, while olpasiran, LY3819469 and SLN360 are small interfering RNAs, all conjugated with a N-acetylgalactosamine molecule. Their ultimate objective is to genetically silence LPA, reduce apo(a) production and lower serum Lp(a) levels. Evidence thus so far demonstrates that monthly subcutaneous administration of a single dose yields optimal results with persisting substantial reductions in Lp(a) levels, potentially enhancing CVD risk reduction. The Lp(a) reduction achieved with novel RNA agents may exceed 95%. The results of ongoing and future clinical trials are eagerly anticipated, and it is hoped that guidelines for the tailored management of Lp(a) levels with these novel agents may not be far off.

Novel and future lipid-modulating therapies for the prevention of cardiovascular disease

Lowering the levels of LDL cholesterol in the plasma has been shown to reduce the risk of atherosclerotic cardiovascular disease (ASCVD). Several other lipoproteins, such as triglyceride-rich lipoproteins, HDL and lipoprotein(a) are associated with atherosclerosis and ASCVD, with strong evidence supporting causality for some. In this Review, we discuss novel and upcoming therapeutic strategies targeting different pathways in lipid metabolism to potentially attenuate the risk of cardiovascular events. Key proteins involved in lipoprotein metabolism, such as PCSK9, angiopoietin-related protein 3, cholesteryl ester transfer protein and apolipoprotein(a), have been identified as viable targets for therapeutic intervention through observational and genetic studies. These proteins can be targeted using a variety of approaches, such as protein inhibition or interference, inhibition of translation at the mRNA level (with the use of antisense oligonucleotides or small interfering RNA), and the introduction of loss-of-function mutations through base editing. These novel and upcoming strategies are complementary to and could work synergistically with existing therapies, or in some cases could potentially replace therapies, offering unprecedented opportunities to prevent ASCVD. Moreover, a major challenge in the prevention and treatment of non-communicable diseases is how to achieve safe, long-lasting reductions in causal exposures. This challenge might be overcome with approaches such as small interfering RNAs or genome editing, which shows how far the field has advanced from when the burden of achieving this goal was placed upon patients through rigorous adherence to daily small-molecule drug regimens.

[Primary disorders of lipid metabolism: their place in current dyslipidemia guidelines and treatment innovations]

According to current guidelines, the selection and intensity of lipid-effective therapies are based on the risk to be treated. The sole clinical categories of primary and secondary prevention of cardiovascular diseases result in over- and under-treatment, which may be a contributory cause of incomplete implementation of current guidelines in everyday practice. For the extent of benefit in cardiovascular outcome studies with lipid-lowering drugs, the importance of dyslipdemia for the pathogenesis of atherosclerosis-related diseases is crucial. Primary lipid metabolism disorders are characterized by life-long increased exposure to atherogenic lipoproteins. This article describes the relevance of new data for low density lipoprotein-effective therapy: inhibition of proprotein convertase subtilisin/kexin type 9 (PCSK9), adenosine triphosphate (ATP) citrate lyase with bempedoic acid, and ANGPTL3 with special consideration of primary lipid metabolism disorders, which are insufficiently taken into account, or not taken into account at all, in current guidelines. This is due to their apparently low prevalence rate and thus the lack of large outcome studies. The authors also discuss the consequences of increased lipoprotein (a), which cannot be sufficiently reduced until the ongoing intervention studies examining antisense oligonucleotides and small interfering RNA (siRNA) against apolipoprotein (a) are completed. Another challenge in practice is the treatment of rare, massive hypertriglyceridemia, especially with the aim of preventing pancreatitis. For this purpose, the apolipoprotein C3 (ApoC3) antisense oligonucleotide volenasorsen is available, which binds to the mRNA for ApoC3 and lowers triglycerides by around three quarters.

Genetics-based risk scores for prediction of premature coronary artery disease

Premature coronary artery disease (CAD) is endemic in India. Global Burden of Diseases study has reported that it led to 286,000 deaths in 2019 in India. Many of these patients have standard risk factors but a third have none. Clinical risk algorithms and imaging provide limited risk information in premature CAD. CAD is multifactorial and studies have now focused on the predictive capability of clusters of genes and single nucleotide polymorphisms (SNPs) using gene risk score (GRS). Older studies combined data from 10 to 12 genes and 100-500 SNPs to calculate GRS, however, following the advent of genome-wide association studies (GWAS), millions of SNPs have been incorporated. Studies have reported that GWAS-based GRS may be more discriminative than conventional tools. Recent studies, especially among South Asians, have reported that GRS improves net reclassification by 15% (12-19%) for younger individuals. Aggressive lifestyle interventions and lipid-lowering therapies can ameliorate risk in high-GRS individuals and potentially prevent premature CAD.

Atherosclerotic Disease: Pathogenesis and Approaches to Management

Atherosclerotic disease, including stroke and myocardial infarction, is the leading cause of morbidity and mortality worldwide. Atherosclerotic plaque formation occurs in the setting of excess oxidative and hemodynamic stress and is perpetuated by smoking, poor diet, dyslipidemia, hypertension, and diabetes. Plaque may rupture, resulting in acute thrombotic events. Smoking cessation, lifestyle modification, risk factor optimization, and antithrombotic therapies are the mainstays of atherosclerotic disease management and are the cornerstones to reduce morbidity and mortality in this high-risk patient population. Novel therapeutics are in development and will add to the growing armamentarium available to physicians who manage atherosclerotic disease.

Advances in Treatment of Dyslipidemia

Dyslipidemias have emerged as prevalent disorders among patients, posing significant risks for the development and progression of cardiovascular diseases. These conditions are characterized by elevated levels of total cholesterol (TC), triglycerides (TGs), and low-density lipoprotein cholesterol (LDL-C). This review delves into the current treatment approach, focusing on equalizing these parameters while enhancing the overall quality of life for patients. Through an extensive analysis of clinical trials, we identify disorders that necessitate alternative treatment strategies, notably familial hypercholesterolemia. The primary objective of this review is to consolidate existing information concerning drugs with the potential to revolutionize dyslipidemia management significantly. Among these promising pharmaceuticals, we highlight alirocumab, bempedoic acid, antisense oligonucleotides, angiopoietin-like protein inhibitors, apolipoprotein C-III (APOC3) inhibitors, lomitapide, and cholesterol ester transfer protein (CETP) inhibitors. Our review demonstrates the pivotal roles played by each of these drugs in targeting specific parameters of lipid metabolism. We outline the future landscape of dyslipidemia treatment, envisaging a more tailored and effective therapeutic approach to address this widespread medical concern.

DNA and RNA Molecules as a Foundation of Therapy Strategies for Treatment of Cardiovascular Diseases

There has always been a tendency of medicine to take an individualised approach to treating patients, but the most significant advances were achieved through the methods of molecular biology, where the nucleic acids are in the limelight. Decades of research of molecular biology resulted in setting medicine on a completely new platform. The most significant current research is related to the possibilities that DNA and RNA analyses can offer in terms of more precise diagnostics and more subtle stratification of patients in order to identify patients for specific therapy treatments. Additionally, principles of structure and functioning of nucleic acids have become a motive for creating entirely new therapy strategies and an innovative generation of drugs. All this also applies to cardiovascular diseases (CVDs) which are the leading cause of mortality in developed countries. This review considers the most up-to-date achievements related to the use of translatory potential of DNA and RNA in treatment of cardiovascular diseases, and considers the challenges and prospects in this field. The foundations which allow the use of translatory potential are also presented. The first part of this review focuses on the potential of the DNA variants which impact conventional therapies and on the DNA variants which are starting points for designing new pharmacotherapeutics. The second part of this review considers the translatory potential of non-coding RNA molecules which can be used to formulate new generations of therapeutics for CVDs.

Administration of insulin like growth factor I (IGFI) lowers serum lipoprotein(a)-impact on atherosclerotic cardiovascular disease

Insulin like growth factor I (IGFI) secreted by the liver upon stimulation by pituitary growth hormone (GH) acts as the most important growth stimulating hormone in children. The present review presents evidence that among its additional metabolic effects, IGF-I suppresses the synthesis of lipoprotein(a) [Lp(a)], an independent risk factor for atherosclerotic cardiovascular disease. In view of this property, it is suggested that the addition of IGF-I to the armamentarium of hyperlipoproteinemia treatment should be considered.

Daring to dream: Targeting lipoprotein(a) as a causal and risk-enhancing factor

Lipoprotein(a) [Lp(a)], a distinct lipoprotein class, has become a major focus for cardiovascular research. This review is written in light of the recent guideline and consensus statements on Lp(a) and focuses on 1) the causal association between Lp(a) and cardiovascular outcomes, 2) the potential mechanisms by which elevated Lp(a) contributes to cardiovascular diseases, 3) the metabolic insights on the production and clearance of Lp(a) and 4) the current and future therapeutic approaches to lower Lp(a) concentrations. The concentrations of Lp(a) are under strict genetic control. There exists a continuous relationship between the Lp(a) concentrations and risk for various endpoints of atherosclerotic cardiovascular disease (ASCVD). One in five people in the Caucasian population is considered to have increased Lp(a) concentrations; the prevalence of elevated Lp(a) is even higher in black populations. This makes Lp(a) a cardiovascular risk factor of major public health relevance. Besides the association between Lp(a) and myocardial infarction, the relationship with aortic valve stenosis has become a major focus of research during the last decade. Genetic studies provided strong support for a causal association between Lp(a) and cardiovascular outcomes: carriers of genetic variants associated with lifelong increased Lp(a) concentration are significantly more frequent in patients with ASCVD. This has triggered the development of drugs that can specifically lower Lp(a) concentrations: mRNA-targeting therapies such as anti-sense oligonucleotide (ASO) therapies and short interfering RNA (siRNA) therapies have opened new avenues to lower Lp(a) concentrations more than 95%. Ongoing Phase II and III clinical trials of these compounds are discussed in this review.

Cardiovascular outcomes in patients with coronary artery disease and elevated lipoprotein(a): implications for the OCEAN(a)-outcomes trial population

Aims

The ongoing Olpasiran Trials of Cardiovascular Events and Lipoprotein(a) Reduction [OCEAN(a)]-Outcomes trial is evaluating whether Lp(a) lowering can reduce the incidence of cardiovascular events among patients with prior myocardial infarction (MI) or percutaneous coronary intervention (PCI) and elevated Lp(a) (≥200 nmol/L). The purpose of this study is to evaluate the association of elevated Lp(a) with cardiovascular outcomes in an observational cohort resembling the OCEAN(a)-Outcomes trial main enrolment criteria.

Methods and results

This study included patients aged 18-85 years with Lp(a) measured as part of their clinical care between 2000 and 2019. While patients were required to have a history of MI, or PCI, those with severe kidney dysfunction or a malignant neoplasm were excluded. Elevated Lp(a) was defined as ≥200 nmol/L consistent with the OCEAN(a)-Outcomes trial. The primary outcome was a composite of coronary heart disease death, MI, or coronary revascularization. Natural language processing algorithms, billing and ICD codes, and laboratory data were employed to identify outcomes and covariates. A total of 3142 patients met the eligibility criteria, the median age was 61 (IQR: 52-73) years, 28.6% were women, and 12.3% had elevated Lp(a). Over a median follow-up of 12.2 years (IQR: 6.2-14.3), the primary composite outcome occurred more frequently in patients with versus without elevated Lp(a) [46.0 vs. 38.0%, unadjHR = 1.30 (95% CI: 1.09-1.53), P = 0.003]. Following adjustment for measured confounders, elevated Lp(a) remained independently associated with the primary outcome [adjHR = 1.33 (95% CI: 1.12-1.58), P = 0.001].

Conclusion

In an observational cohort resembling the main OCEAN(a)-Outcomes Trial enrolment criteria, patients with an Lp(a) ≥200 nmol/L had a higher risk of cardiovascular outcomes.

Lipoprotein(a) and diet-a challenge for a role of saturated fat in cardiovascular disease risk reduction?

In this perspective, we discuss new evidence relating to current dietary recommendations to reduce SFA intake to modulate an individual's global risk of CVD. Although it is well established that lowering dietary SFA intake has a beneficial effect on LDL cholesterol concentrations, findings increasingly indicate an opposite effect on lipoprotein(a) [Lp(a)] concentrations. In recent years, many studies have firmly established a role for an elevated Lp(a) concentration as a genetically regulated, causal, and prevalent risk factor for CVD. However, there is less awareness of the effect of dietary SFA intake on Lp(a) concentrations. This study discusses this issue and highlights the contrasting effect of reducing dietary SFA intake on LDL cholesterol and Lp(a), 2 highly atherogenic lipoproteins. This calls attention to the need for precision nutrition approaches that move beyond a "one-size-fits-all" approach. To illustrate the contrast, we describe the dynamic contributions of Lp(a) and LDL cholesterol concentrations to CVD risk during interventions with a low-SFA diet, with the hope that this will stimulate further studies and discussions regarding dietary management of CVD risk.

Current Management and Future Perspectives in the Treatment of Lp(a) with a Focus on the Prevention of Cardiovascular Diseases

Lipoprotein(a) [Lp(a)] is a lipid molecule with atherogenic, inflammatory, thrombotic, and antifibrinolytic effects, whose concentrations are predominantly genetically determined. The association between Lp(a) and cardiovascular diseases (CVDs) has been well-established in numerous studies, and the ability to measure Lp(a) levels is widely available in the community. As such, there has been increasing interest in Lp(a) as a therapeutic target for the prevention of CVD. The impact of the currently available lipid-modifying agents on Lp(a) is modest and heterogeneous, except for the monoclonal antibody proprotein convertase subtilisin/kexin type 9 inhibitors (PCSK9i), which demonstrated a significant reduction in Lp(a) levels. However, the absolute reduction in Lp(a) to significantly decrease CVD outcomes has not been definitely established, and the magnitude of the effect of PCSK9i seems insufficient to directly reduce the Lp(a)-related CVD risk. Therefore, emerging therapies are being developed that specifically aim to lower Lp(a) levels and the risk of CVD, including RNA interference (RNAi) agents, which have the capacity for temporary and reversible downregulation of gene expression. This review article aims to summarize the effects of Lp(a) on CVD and to evaluate the available evidence on established and emerging therapies targeting Lp(a) levels, focusing on the potential reduction of CVD risk attributable to Lp(a) concentrations.

On-treatment platelet reactivity through the thromboxane A2 or P2Y12 platelet receptor pathways is not affected by pelacarsen

BACKGROUND

Pelacarsen decreases plasma levels of lipoprotein(a) [Lp(a)] and oxidized phospholipids (OxPL). It was previously reported that pelacarsen does not affect the platelet count. We now report the effect of pelacarsen on on-treatment platelet reactivity.

METHODS

Subjects with established cardiovascular disease and screening Lp(a) levels ≥60 mg per deciliter (~ ≥150 nmol/L) were randomized to receive pelacarsen (20, 40, or 60 mg every 4 weeks; 20 mg every 2 weeks; or 20 mg every week), or placebo for 6-12 months. Aspirin Reaction Units (ARU) and P2Y12 Reaction Units (PRU) were measured at baseline and the primary analysis timepoint (PAT) at 6 months.

RESULTS

Of the 286 subjects randomized, 275 had either an ARU or PRU test, 159 (57.8%) were on aspirin alone and 94 (34.2%) subjects were on dual anti-platelet therapy. As expected, the baseline ARU and PRU were suppressed in subjects on aspirin or on dual anti-platelet therapy, respectively. There were no significant differences in baseline ARU in the aspirin groups or in PRU in the dual anti-platelet groups. At the PAT there were no statistically significant differences in ARU in subjects on aspirin or PRU in subjects on dual anti-platelet therapy among any of the pelacarsen groups compared to the pooled placebo group (p > 0.05 for all comparisons).

CONCLUSION

Pelacarsen does not modify on-treatment platelet reactivity through the thromboxane A₂ or P2Y12 platelet receptor pathways.

Frequent questions and responses on the 2022 lipoprotein(a) consensus statement of the European Atherosclerosis Society

In 2022, the European Atherosclerosis Society (EAS) published a new consensus statement on lipoprotein(a) [Lp(a)], summarizing current knowledge about its causal association with atherosclerotic cardiovascular disease (ASCVD) and aortic stenosis. One of the novelties of this statement is a new risk calculator showing how Lp(a) influences lifetime risk for ASCVD and that global risk may be underestimated substantially in individuals with high or very high Lp(a) concentration. The statement also provides practical advice on how knowledge about Lp(a) concentration can be used to modulate risk factor management, given that specific and highly effective mRNA-targeted Lp(a)-lowering therapies are still in clinical development. This advice counters the attitude: "Why should I measure Lp(a) if I can't lower it?". Subsequent to publication, questions have arisen relating to how the recommendations of this statement impact everyday clinical practice and ASCVD management. This review addresses 30 of the most frequently asked questions about Lp(a) epidemiology, its contribution to cardiovascular risk, Lp(a) measurement, risk factor management and existing therapeutic options.

Triglyceride-rich lipoproteins, remnant-cholesterol, and atherosclerotic cardiovascular disease

PURPOSE OF REVIEW

Despite indisputable role of LDL-C lowering, a considerable residual risk for atherosclerotic cardiovascular disease (ASCVD) persists. The precise mechanism(s) underlying this phenomenon remain unclear. Triglyceride-rich lipoproteins (TRL) appear to be one of the main mediators, based on the genetic and epidemiologic data. However, whether this is caused by direct effects of Triglycerides or other components of TRL remains uncertain. The cholesterol component of TRL remnants (Rem-C) has been proposed as a more pertinent mediator of the increased risk associated with high triglycerides.

RECENT FINDINGS

Several long-term observational studies have shown a significant relationship between Rem-C and ASCVD events, compared with other triglyceride-related parameters. Recent trials have shown that lowering of triglyceride levels by various agents, including fibrates and omega-3 fatty acids, in statin-treated subjects, did not explain the reduction in ASCVD events. In a large clinical trial with pemafibrate, a highly selective PPAR-α agonist, in type 2 diabetes and elevated triglycerides, the reduction in triglycerides was accompanied by a significant increase in LDL-C and Apo-B levels, despite a reduction in Rem-C, and no effect on ASCVD events.

SUMMARY

Elevated Rem-C as a risk determinant, with LDL-C at goal, requires additional studies in clinical trials. Standardization and accuracy of Rem-C assays (calculated versus direct method) is also needed.

Advances in Clinical Cardiology 2022: A Summary of Key Clinical Trials

INTRODUCTION

Over the course of 2022, numerous key clinical trials with valuable contributions to clinical cardiology were published or presented at major international conferences. This review seeks to summarise these trials and to reflect on their clinical context.

METHODS

The authors reviewed clinical trials presented at major cardiology conferences during 2022, including the American College of Cardiology (ACC), European Association for Percutaneous Cardiovascular Interventions (EuroPCR), European Society of Cardiology (ESC), Transcatheter Cardiovascular Therapeutics (TCT), American Heart Association (AHA), European Heart Rhythm Association (EHRA), Society for Cardiovascular Angiography and Interventions (SCAI), TVT-The Heart Summit (TVT) and Cardiovascular Research Technologies (CRT). Trials with a broad relevance to the cardiology community and those with potential to change current practice were included.

RESULTS

A total of 93 key cardiology clinical trials were identified for inclusion. Interventional cardiology data included trials evaluating the use of new generation novel stent technology and new intravascular physiology strategies such as quantitative flow ratio (QFR) to guide revascularisation in stable and unstable coronary artery disease. New trials in acute coronary syndromes and intervention focused on long-term outcomes of optimal medical therapy (OMT), revascularisation in ischaemic dysfunction and left main (LM) intervention. Structural intervention trials included latest data on optimal timing and anticoagulation strategies in transcatheter aortic valve replacement (TAVR), in addition to expanding evidence in mitral and tricuspid valve interventions. Heart failure data included trials with sodium-glucose cotransporter 2 (SGLT2) inhibitors, iron replacement and novel drugs such as omecamtiv. Prevention trials included new data on proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors and polypill strategies. In electrophysiology, new data regarding optimal timing of ablative therapy for atrial fibrillation (AF) in addition to novel screening strategies were evaluated.

CONCLUSION

This article presents a summary of key clinical cardiology trials published and presented during the past year and should be of interest to both practising clinicians and researchers.

U-shaped association between low-density lipoprotein cholesterol levels and risk of all-cause mortality mediated by post-stroke infection in acute ischemic stroke

During the acute stage of ischemic stroke, it remains unclear how to interpret the low low-density lipoprotein cholesterol (LDL-C) level. We aimed to evaluate the association between LDL-C levels, post-stroke infection, and all-cause mortality. 804,855 ischemic stroke patients were included. Associations between LDL-C levels, infection, and mortality risk were estimated by multivariate logistic regression models and displayed by restricted cubic spline curves. Mediation analysis was performed under counterfactual framework to elucidate the mediation effect of post-stroke infection. The association between LDL-C and mortality risk was U-shaped. The nadir in LDL-C level with the lowest mortality risk was 2.67 mmol/L. Compared with the group with LDL-C = 2.50-2.99 mmol/L, the multivariable-adjusted odds ratio for mortality was 2.22 (95% confidence intervals (CI): 1.77-2.79) for LDL-C <1.0 mmol/L and 1.22 (95% CI: 0.98-1.50) for LDL-C ≥5.0 mmol/L. The association between LDL-C and all-cause mortality was 38.20% (95% CI: 5.96-70.45, P = 0.020) mediated by infection. After stepwise excluding patients with increasing numbers of cardiovascular risk factors, the U-shaped association between LDL-C and all-cause mortality and the mediation effects of infection remained consistent with the primary analysis, but the LDL-C interval with the lowest mortality risk increased progressively. The mediation effects of infection were largely consistent with the primary analysis in subgroups of age ≥65 years, female, body mass index <25 kg/m², and National Institutes of Health Stroke Scale ≥16. During the acute stage of ischemic stroke, there is a U-shaped association between LDL-C level and all-cause mortality, where post-stroke infection is an important mediating mechanism.

Effects of Lipid-Modifying and Other Drugs on Lipoprotein(a) Levels-Potent Clinical Implications

The past few years have shown an ongoing interest in lipoprotein(a) (Lp(a)), a lipid molecule that has been proven to have atherogenic, thrombogenic, and inflammatory properties. Several lines of evidence, indeed, have demonstrated an increased risk of cardiovascular disease as well as calcific aortic valve stenosis in patients with elevated Lp(a) levels. Statins, the mainstay of lipid-lowering therapy, slightly increase Lp(a) levels, while most other lipid-modifying agents do not significantly alter Lp(a) concentrations, except for proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors. The latter have been shown to reduce Lp(a) levels; however, the clinical significance of this effect has not been clearly elucidated. Of note, the pharmaceutical lowering of Lp(a) may be achieved with novel treatments specifically designed for this purpose (i.e., antisense oligonucleotides (ASOs) and small interfering RNAs (siRNAs)). Large clinical trials with cardiovascular outcomes with these agents are ongoing, and their results are eagerly awaited. Furthermore, several non-lipid-modifying drugs of various classes may influence Lp(a) concentrations. We have searched MEDLINE, EMBASE, and CENTRAL databases up to 28 January 2023 and summarized the effects of established and emerging lipid-modifying drugs and other medications on Lp(a) levels. We also discuss the potent clinical implications of these alterations.

How do we forecast tomorrows' transfusion: Non-transfusional hemotherapy

Hemotherapy is the treatment of diseases by the use of blood or blood products from blood donation (by others of for oneself). It is clear that blood components transfusion represents the most important part of the activities of the professionals (doctors, nurses, technicians…) working in hemotherapy. But there are others forms of hemotherapy that are steadily growing, that we will discuss: plasma exchange, mononuclear cells collections for cellular therapies, extracorporeal photoapheresis, ABO antigen specific immunoadsorption and autologous platelet lysate.

Lipoprotein(a) Is Associated With the Progression and Vulnerability of New-Onset Carotid Atherosclerotic Plaque

BACKGROUND

Although important progress has been made in understanding Lp(a) (lipoprotein[a])-mediated stroke risk, the contribution of Lp(a) to the progression of vulnerable plaque features associated with stroke risk remains unclear. This study aims to evaluate whether Lp(a) is associated with carotid plaque progression, new-onset plaque features, and plaque vulnerability in a prospective community-based cohort study.

METHODS

Baseline Lp(a) levels were measured using latex-enhanced turbidimetric immunoassay among 804 participants aged 45 to 74 years and free of cardiovascular disease in the Chinese Multi-provincial Cohort Study-Beijing project. Carotid atherosclerosis was measured twice by B-mode ultrasonography over a 10-year interval during the 2002 and 2012 surveys to assess the progression of total, vulnerable and stable plaques, and plaque vulnerability. The total plaque area and plaque vulnerability score were calculated.

RESULTS

The median baseline Lp(a) level was 10.20 mg/dL (interquartile range, 6.20 to 17.18 mg/dL). Modified Poisson regression analysis showed that Lp(a) ≥50 mg/dL was significantly associated with 10-year progression of total carotid plaque (relative risk [RR], 1.41 [95% CI, 1.21-1.64]; E-value=2.17), vulnerable plaque (RR, 1.93 [95% CI, 1.54-2.41]), and stable plaque (RR, 1.51 [95% CI, 1.11-2.07]) compared with Lp(a) <50 mg/dL. Moreover, among participants without plaque at baseline, Lp(a) ≥50 mg/dL was related to an increased total plaque area (β=0.36 [95% CI, 0.06-0.65]; P=0.018) and increased plaque vulnerability score (β=0.30 [95% CI, 0.01-0.60]; P=0.045) in multivariable linear regression.

CONCLUSIONS

Elevated Lp(a) levels were associated with 10-year carotid plaque progression and plaque vulnerability, providing a basis for Lp(a) as a treatment target for stroke prevention.

Clinical Trial Design for Lipoprotein(a)-Lowering Therapies: JACC Focus Seminar 2/3

Lipoprotein(a) [Lp(a)] is a source of residual risk in patients with atherosclerotic cardiovascular disease (ASCVD). Clinical trials of fully human monoclonal antibodies targeting proprotein convertase subtilisin kexin 9 have shown that reductions in Lp(a) concentrations may be a predictor of event reduction with this class of cholesterol-lowering therapy. With the advent of selective therapies targeting Lp(a) such as antisense oligonucleotides, small-interfering RNA-based therapies, and gene editing, lowering of Lp(a) may lead to reduction in ASCVD. The phase 3 Lp(a)HORIZON (Assessing the Impact of Lipoprotein(a) Lowering with TQJ230 on Major Cardiovascular Events in Patients With CVD) outcomes trial is currently testing the effect of pelacarsen, an antisense oligonucleotide, on ASCVD risk. Olpasiran is a small-interfering RNA that is in a phase 3 clinical trial. As these therapies enter clinical trials, challenges in trial design will have to be addressed to optimize patient selection and outcomes.

New Insights into Pathophysiology and New Risk Factors for ACS

Cardiovascular disease still represents the main cause of mortality worldwide. Despite huge improvements, atherosclerosis persists as the principal pathological condition, both in stable and acute presentation. Specifically, acute coronary syndromes have received substantial research and clinical attention in recent years, contributing to improve overall patients' outcome. The identification of different evolution patterns of the atherosclerotic plaque and coronary artery disease has suggested the potential need of different treatment approaches, according to the mechanisms and molecular elements involved. In addition to traditional risk factors, the finer portrayal of other metabolic and lipid-related mediators has led to higher and deep knowledge of atherosclerosis, providing potential new targets for clinical management of the patients. Finally, the impressive advances in genetics and non-coding RNAs have opened a wide field of research both on pathophysiology and the therapeutic side that are extensively under investigation.

Lipoprotein (a), Inflammation, and Atherosclerosis

Growing evidence has shown that high levels of lipoprotein (a) (Lp(a)) and chronic inflammation may be responsible for the residual risk of cardiovascular events in patients managed with an optimal evidence-based approach. Clinical studies have demonstrated a correlation between higher Lp(a) levels and several atherosclerotic diseases including ischemic heart disease, stroke, and degenerative calcific aortic stenosis. The threshold value of Lp(a) serum concentrations associated with a significantly increased cardiovascular risk is >125 nmol/L (50 mg/dL). Current available lipid-lowering drugs have modest-to-no impact on Lp(a) levels. Chronic inflammation is a further condition potentially implicated in residual cardiovascular risk. Consistent evidence has shown an increased risk of cardiovascular events in patients with high sensitivity C reactive protein (>2 mg/dL), an inflammation biomarker. A number of anti-inflammatory drugs have been investigated in patients with or at risk of cardiovascular disease. Of these, canakinumab and colchicine have been found to be associated with cardiovascular risk reduction. Ongoing research aimed at improving risk stratification on the basis of Lp(a) and vessel inflammation assessment may help refine patient management. Furthermore, the identification of these conditions as cardiovascular risk factors has led to increased investigation into diagnostic and therapeutic strategies targeting them in order to reduce atherosclerotic cardiovascular disease burden.

A Systematic Review on the Risk Modulators of Myocardial Infarction in the "Young"-Implications of Lipoprotein (a)

The presence of a myocardial infarction at a younger age is of special interest, considering the psychological and socioeconomic impact, as well as long-term morbidity and mortality. However, this group has a unique risk profile, with less traditional cardiovascular risk factors that are not well studied. This systematic review aims to evaluate traditional risk factors of myocardial infarction in the "young", highlighting the clinical implications of lipoprotein (a). We performed a comprehensive search using Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) standards; we systematically searched the PubMed, EMBASE, and Science Direct Scopus databases, using the terms: "myocardial infarction", "young", "lipoprotein (a)", "low-density lipoprotein", "risk factors". The search identified 334 articles which were screened, and, at the end, 9 original research articles regarding the implications of lipoprotein (a) in myocardial infarction in the "young" were included in the qualitative synthesis. Elevated lipoprotein (a) levels were independently associated with an increased risk of coronary artery disease, especially in young patients, where this risk increased by threefold. Thus, it is recommended to measure the lipoprotein (a) levels in individuals with suspected familial hypercholesterolaemia or with premature atherosclerotic cardiovascular disease and no other identifiable risk factors, in order to identify patients who might benefit from a more intensive therapeutic approach and follow-up.

Lipoprotein(a) distribution and its association with carotid arteriopathy in the Chinese population

BACKGROUND AND AIMS

The distribution of lipoprotein(a) [Lp(a)] has not been well-studied in a large population in China. The relationship between Lp(a) and carotid atherosclerosis remains undefined. In this study, we aimed to investigate the distribution of Lp(a) levels and to assess their association with carotid arteriopathy in China.

METHODS

In this cross-sectional study, 411,634 adults with Lp(a) measurements from 22 health check-up centers were used to investigate Lp(a) distribution in China. Among participants with Lp(a) data, carotid ultrasound was performed routinely at seven health check-up centers covering 75,305 subjects. Carotid intima-media thickness (cIMT) and carotid plaque were used as surrogate biomarkers of carotid arteriopathy. The multivariate logistic regression model was applied to evaluate the association of increased Lp(a) levels with carotid arteriopathy.

RESULTS

The distribution of Lp(a) concentrations was right-skewed, with a median concentration of 10.60 mg/dL. The proportions of Lp(a) levels ≥30 mg/dL and ≥50 mg/dL were 16.75% and 7.10%, respectively. The median Lp(a) level was higher in females individuals in northern China, and increased with age. Spearman's analysis revealed weak correlations between the Lp(a) concentration as a continuous variable and other lipid profiles. The multiple logistic regression analysis showed that participants with Lp(a) levels ≥50 mg/dL had an increased risk of cIMT ≥1.0 mm (OR = 1.138, 95% CI, 1.071-1.208) and carotid plaque (OR = 1.296, 95% CI, 1.219-1.377) compared with those with Lp(a) levels <50 mg/dL.

CONCLUSIONS

This is the first study of the Lp(a) distribution in a large population in China. Our findings revealed a positive association between elevated Lp(a) levels (≥50 mg/dL) and increased prevalence of carotid atherosclerosis, which implies an increased risk of cardiovascular disease in the future.

Secondary Cardiovascular Prevention after Acute Coronary Syndrome: Emerging Risk Factors and Novel Therapeutic Targets

The control of cardiovascular risk factors, the promotion of a healthy lifestyle, and antithrombotic therapy are the cornerstones of secondary prevention after acute coronary syndrome (ACS). However, many patients have recurrent ischemic events despite the optimal control of traditional modifiable risk factors and the use of tailored pharmacological therapy, including new-generation antiplatelet and lipid-lowering agents. This evidence emphasizes the importance of identifying novel risk factors and targets to optimize secondary preventive strategies. Lipoprotein(a) (Lp(a)) has emerged as an independent predictor of adverse events after ACS. New molecules such as anti-PCSK9 monoclonal antibodies, small interfering RNAs, and antisense oligonucleotides can reduce plasma Lp(a) levels and are associated with a long-term outcome benefit after the index event. The inflammatory stimulus and the inflammasome, pivotal elements in the development and progression of atherosclerosis, have been widely investigated in patients with coronary artery disease. More recently, randomized clinical trials including post-ACS patients treated with colchicine and monoclonal antibodies targeting cytokines yielded promising results in the reduction in major cardiovascular events after an ACS. Gut dysbiosis has also raised great interest for its potential pathophysiological role in cardiovascular disease. This evidence, albeit preliminary and needing confirmation by larger population-based studies, suggests the possibility of targeting the gut microbiome in particularly high-risk populations. The risk of recurrent ischemic events after ACS is related to the complex interaction between intrinsic predisposing factors and environmental triggers. The identification of novel risk factors and targets is fundamental to customizing patient clinical management with a precision medicine perspective.